Naturalistic study of rider's behaviour in initial training in France: Evidence of limitations in the educational content

This paper analyses motorcycle educational content in a number of French motorcycle schools on the basis of a naturalistic study of riders’ and trainers’ behaviour. The aim is to specify the situations delivered in motorcycle schools and to study the rider's activity in these situations. The methodology includes ethnographic observation within the motorcycle schools and the longitudinal monitoring of 14 trainee motorcyclists during their initial training. The training situations were described by the combination of audio–visual recordings and interviews data (i.e. concomitant or interruptive verbalization, and self-confrontation data). The results permit to (1) compare the “real” and “official” durations of track and on-road training, (2) characterize the real training situations, (3) describe the preferred forms of instruction, and (4) conduct an in-depth analysis of the situations used during training in traffic. The discussion show, in first, the poverty of the training situations which are based on the repetition of the exercises in the test, and, in second, disparities between the riding situations encountered during training and the demands made by riding in natural traffic. The usefulness and the applications of this type of approach – based on the integration of the rider's point of view notably by self-confrontation interview – for understanding real riding behaviours and how such approaches could supplement vehicle-based data are discussed in a large conclusion.     

Statistical analysis of concrete transport properties

Results of a statistical analysis of transport properties measurements carried out on a number of concrete mixtures are presented. Migration and drying experiments were performed to evaluate the ionic diffusion coefficients and permeability of concrete mixtures. Seven concrete mixtures were tested. The mixtures were either batched under laboratory conditions or sampled from construction sites. For each mixture, approximately eighty concrete samples from a single batch were tested. Ionic diffusion coefficients were calculated by analyzing the evolution of the electrical current passing through concrete samples during the migration tests. Calculations took into account the volume of permeable pores of the materials and the pore solution chemistry. Permeability was calculated from mass loss measured during drying tests. The study indicates that the coefficient of variation of ionic diffusion coefficients is 11.1 % on average, with a maximum of 23.5 %, and that the coefficient of variation of permeability is 20.6 % on average, with a maximum of 37.3 %.     

L'Alphabétisation technoscientifique et la démocratisation de la démocratie

Résumé

La métaphore du changement de guide proposée par Fensham (2002a) constitue un véritable faux‐fuyant. Cette solution aux présumés problèmes d'une alphabétisation technoscientifique pour tous et toutes fait l'impasse sur une interrogation plus générale à propos de la socialite des technosciences. Ainsi, l'auteur reconduit la séculaire séparation entre le monde de la science et celui de la société, qui justifie que seuls des ? experts ?, scientifiques ou sociétaux, puissent servir de médiateurs entre ces univers incommensurables. Il élimine donc d'emblée, en évoquant la complexité des problèmes, la possibilité pour les citoyens et les citoyennes ordinaires de s'engager dans les controverses sociotechniques qui traversent inévitablement nos sociétés. En conséquence, il se rabat sur une forme d'alphabétisation technoscientifique à deux vitesses ; l'une pour la populace, l'autre pour une élite qui, à terme, aura le privilège de pénétrer dans l'univers mystérieux et ésotérique de la science. Autrement dit, les contenus des curriculums pourront varier sans que la hiérarchie sociale des savoirs, de même que les pouvoirs forcément politiques des experts, soient menacés.     

Effects of Speeds,Materials, and Tool Rake Angles on Metallic Particle Emission During Orthogonal Cutting

Dry high speed machining has been proposed as a viable and cost-effective process in metal cutting industries. However, it produces fine and ultra-fine metallic particles, also referred to as dust, which can be harmful to the machine-tool operator. The risk associated with exposure to metallic particles increases as the particle size decreases. For machining processes, little data exist on the size and distribution of dust generated during the shaping of materials. In order to reduce or eliminate the generation of these particles, it is necessary to understand how and under which conditions they are formed, as well as to be able to make predictions. In this study, the effects exerted by tool geometry, material, and machining parameters on dust emission were studied experimentally in order to understand the mechanisms of dust generation and to develop a predictive model. The particle sizes studied include the PM2.5 (particles with aerodynamique diameter below 2.5 μm) and a distribution of nanoparticles varying in size from 10 nm to 10 μm. Using dry machining and reducing the amount of dust generated should improve the air quality in machine shops in addition to helping protect the environment.     

Modeling of Particle Emission During Dry Orthogonal Cutting

Because of the risks associated with exposure to metallic particles, efforts are being put into controlling and reducing them during the metal working process. Recent studies by the authors involved in this project have presented the effects of cutting speeds, workpiece material, and tool geometry on particle emission during dry machining; the authors have also proposed a new parameter, named the dust unit (D _u), for use in evaluating the quantity of particle emissions relative to the quantity of chips produced during a machining operation. In this study, a model for predicting the particle emission (dust unit) during orthogonal turning is proposed. This model, which is based on the energy approach combined with the microfriction and the plastic deformation of the material, takes into account the tool geometry, the properties of the worked material, the cutting conditions, and the chip segmentation. The model is validated using experimental results obtained during the orthogonal turning of 6061-T6 aluminum alloy, AISI 1018, AISI 4140 steels, and grey cast iron. A good agreement was found with experimental results. This model can help in designing strategies for reducing particle emission during machining processes, at the source.     

The Examination for Professional Practice in Psychology (EPPP) in the era of evidence-based practice.

Professional psychology has increasingly moved toward evidence-based practice. However, instruments used to assess psychologists seeking licensure, such as the Examination for Professional Practice in Psychology (EPPP), have received relatively little empirical scrutiny. Therefore, the authors evaluated the available evidence in support of the EPPP’s validity and current use as a core component of professional licensure. Although the EPPP has in many ways been extensively evaluated, there is a paucity of criterion, predictive, and incremental validity evidence available. Further, several aspects of the content validation studies were examined, and the authors question whether the EPPP, as currently constructed, can meet its stated goals. Given that the EPPP is a high-stakes examination and given the authors’ best estimate (based on a sample of 16 states) that 35% of applicants fail the examination, it is recommended that the EPPP be more extensively evaluated. An outline of major decision points in this proposed evaluation process is provided, several suggestions for further research are proposed, and the field is encouraged to discuss these issues further. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Optimal and heuristic solution methods for a multiprocessor machine scheduling problem

This paper deals with the scheduling of operations on a multiprocessor machine in the context of shoe manufacturing. Multiprocessor machines are composed of several parallel processors. Unlike parallel machines, the entire machine needs to be stopped whenever a single processor needs a setup. Our industrial partner, one of the major winter-shoe manufacturers in Canada, offers a relatively large variety of models. For each of these models, all the sizes proposed by this manufacturer must be produced in various quantities. Our objective is to schedule the production of the required sizes on the machine's different processors in order to minimize the global makespan, which includes both the production time and the set up time. We first present a mathematical formulation of the problem. Then, we introduce a decomposition procedure based on the mathematical model, and we demonstrate that this procedure is very efficient for small- and medium-size instances. We also propose two construction heuristics and two improvement heuristics for larger problems, and we report the results of our extensive computational experiments to demonstrate the quality of the proposed heuristics in terms of reducing production time and computational effort.     

Materials problems in space

This paper is intended to be a short survey of the materials problems associated with spacecraft design and manufacture. The space environment is first described and compared with the “Spacecraft Environment”, which is dependent upon the characteristic features of each individual vehicle.

Some areas of spacecraft technology, where materials properties are critical, are briefly described; the problems which can arise are then underlined. They are divided between “Classical” problems, not different from those which appear in a number of Earth technologies, and “Specific to Space” problems which are mainly created by vacuum exposure, radiation fluxes and thermal stresses.

The conclusions clearly indicate the necessity for proper methods of materials and processes selection for space applications and show that close cooperation between design engineers and materials specialists is absolutely essential.     

Coastal environment: EC‐cost 48 bioconversion projects and economic aspects

Seaweed has proved to be both a potential resource and a problem for coastal areas. In the framework of the European Communities, a scientific commission was created some 8 years ago, in order to address the matter of seaweed bioconversion in Europe. A book, recently published, represents a fair review and survey of seaweed as a resource in Europe. The matter of seaweed problems and expanded use is now under study in a new programme.

This paper traces back the development and growth of this inter‐European effort and also provides an overview of achievements.